Hello fellow bot coder and welcome to Bots United then!
Do you already have a forum ? If so, we can put a link to it at the bottom of the Bots United forum main page.
For your Steam ID problem, the function you are looking for is pfnGetPlayerAuthID(). And you DO can change the Steam ID of a bot, all you need to do is to pass on your own ID string to this function when the calling entity is one of your bots. For an example of use of this function with bots, see my logfix plugin for metamod (it's available from my site with source code).